A blind area free design method of an omni-directional horizontally polarized antenna

Abstract

The application discloses a non-blind area design method of an omnidirectional horizontal polarization antenna and belongs to the technical field of antenna design. The omnidirectional horizontal polarization antenna is provided with a coaxial circular polarization antenna in the center area; the amplitude and phase difference of the circular polarization antenna and the omnidirectional horizontal polarization antenna are configured, and the amplitude and phase difference between the circular polarization antenna and the omnidirectional horizontal polarization antenna are realized through a corresponding feed network.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of antenna design, and more particularly relates to a blind area free design method of an omnidirectional horizontal polarization antenna. BACKGROUND

[0002] In some application scenarios, an antenna is required to have omnidirectional and full polarization radiation or receiving capability. The design of an omnidirectional vertical polarization antenna is relatively easy to implement, and a straight single pole antenna or a dipole antenna can be used to achieve it. A magnetic dipole can produce omnidirectional horizontal polarization radiation in space, but there is no magnetic dipole in nature. A uniform current loop is generally used to achieve omnidirectional horizontal polarization radiation. Common structures include several uniformly arranged electric dipoles rotating sequentially along the circumferential direction, a circular array of a Vivaldi antenna, or a metal circular ring composed of several circular arc strips connected by a coupling structure. The antenna that uses a uniform current loop to achieve omnidirectional horizontal polarization radiation has good non-circularity and good low-elevation coverage characteristics in the horizontal plane.

[0003] A common shortcoming of dipole antennas is that the pattern has a null in the direction along the central axis of the circular ring. Although the omnidirectional vertical polarization pattern formed by the electric dipole also has a null in the axial direction of the electric dipole, the propagation characteristics of electromagnetic waves determine that there is no vertically polarized incoming wave in this direction, so there is no blind area. However, for an omnidirectional horizontal polarization antenna, the null in the direction along the central axis of the circular ring will form a blind area in the corresponding airspace. SUMMARY

[0004] In view of the above defects or improvement needs of the prior art, the present application provides a blind area free design method of an omnidirectional horizontal polarization antenna, which introduces a coaxial circular polarization antenna to compensate for the radiation blind area of the omnidirectional horizontal polarization antenna in the central axis direction.

[0005] To achieve the above-mentioned purpose, the present application provides a blind area free design method of an omnidirectional horizontal polarization antenna, comprising:

[0006] A circular polarization antenna of the same frequency band is placed in parallel in the central region of the omnidirectional horizontal polarization antenna.

[0007] The amplitude and phase difference of the circular polarization antenna and the omnidirectional horizontal polarization antenna are configured, and the amplitude and phase difference between the circular polarization antenna and the omnidirectional horizontal polarization antenna are realized through a corresponding feed network.

[0008] In some optional embodiments, the size of the circular polarization antenna is determined based on the principle of not blocking the radiation of the omnidirectional horizontal polarization antenna, so that the central axis of the circular polarization antenna and the omnidirectional horizontal polarization antenna coincide.

[0009] In some optional embodiments, the radius of the circular polarization antenna cannot exceed the inner diameter of the circular ring of the omnidirectional horizontal polarization antenna.

[0010] In some alternative embodiments, the configuration principle of the amplitude and phase difference between the circularly polarized antenna and the omnidirectional horizontally polarized antenna is to compromise between the depth of the notch of the radiation pattern and the non-circularity in the horizontal plane.

[0011] In some alternative embodiments, the amplitude and phase difference between the circularly polarized antenna and the omnidirectional horizontally polarized antenna is achieved by a corresponding feed network, which includes:

[0012] Based on the fact that the omnidirectional horizontally polarized antenna has the maximum radiation in the horizontal direction but is a radiation blind area in the vertical direction, and the circularly polarized antenna has less radiation in the horizontal direction but has the maximum radiation in the vertical direction, according to the index requirements of the radiation in the horizontal direction and the vertical direction in the specific application scenario, the amplitude and phase of the feed between the omnidirectional horizontally polarized antenna and the circularly polarized antenna are adjusted to realize the regulation of the radiation pattern shape.

[0013] In some alternative embodiments, the omnidirectional horizontally polarized antenna is in the form of a ring as a whole and is composed of several arc-shaped metal sheets, and a few-shaped slot is excavated at the end of each metal sheet to provide periodic series capacitance and introduce a pair of parallel double wires as a balanced feed balun.

[0014] In some alternative embodiments, the upper surface of the circularly polarized antenna is spliced by a pair of trapezoidal and rectangular composite patches and a pair of crescent-shaped patches, and the lower surface has the same shape as the upper surface and is placed orthogonally to the upper surface.

[0015] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0016] By introducing the coaxial circularly polarized antenna to compensate for the radiation blind area of the omnidirectional horizontally polarized antenna in the central axis direction, the problem of the top space blind area of the antenna view of data communication can be solved. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram of an omnidirectional horizontally polarized antenna provided by an embodiment of the present application;

[0018] Figure 2 is a schematic diagram of a circularly polarized antenna provided by an embodiment of the present application;

[0019] Figure 3 is a schematic diagram of the combined placement of a horizontally polarized antenna and a circularly polarized antenna provided by an embodiment of the present application;

[0020] Figure 4 is a radiation pattern of a combined antenna in the vertical plane provided by an embodiment of the present application;

[0021] Figure 5 is a horizontal pattern of a combined antenna provided by an embodiment of the present application;

[0022] Figure 6 is a three-dimensional pattern provided by an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0024] As shown in Figure 1 , the omnidirectional horizontal polarization antenna designed by the present application is printed on a circular Arlon AD270 dielectric plate with a thickness of 0.6 mm, a dielectric constant of 2.7 and a loss tangent of 0.0023. The whole antenna is in a ring type distribution, which is composed of 8 arc-shaped metal sheets. The end of each metal sheet is excavated with a "Ji" type slot to provide a periodic series capacitance, and a pair of parallel double wires is introduced as a balun for balanced feed. Among them, the uniform current distribution on the antenna can be realized by adjusting the length of each arc-shaped metal sheet and the size of the "Ji" type slot, and the omnidirectional horizontal polarization radiation effect can be achieved.

[0025] In order to realize the omnidirectional horizontal polarization antenna, a circular polarization antenna placed above the horizontal polarization antenna is needed, but the radius of the circular polarization antenna cannot exceed the inner diameter of the omnidirectional horizontal polarization antenna, otherwise it will have a serious impact on the impedance matching and pattern of the horizontal polarization unit. The designed circular polarization antenna is shown in Figure 2 . The antenna is printed on an Arlon AD1000 dielectric plate with a thickness of 1.2 mm, a relative dielectric constant of 10.2 and a loss tangent of 0.0023. The upper surface of the antenna is composed of a pair of trapezoidal and rectangular composite patches and a pair of crescent-shaped patches, and the lower surface is the same shape as the upper surface, and the two are placed orthogonally.

[0026] The circular polarization antenna and the omnidirectional horizontal polarization antenna are placed in parallel, and the circular polarization radiation field and the radiation field of the horizontal polarization antenna are superimposed with appropriate amplitude and phase difference, which not only makes up for the blind area of the horizontal polarization field, but also ensures the approximate omnidirectional radiation characteristics in the horizontal plane. Due to the characteristics of the circular polarization antenna, while filling the blind area of the horizontal polarization antenna, the original performance of the horizontal polarization antenna is not greatly affected. Figure 3 is a side view of the combination of the two antennas, and the distance h6 between the upper surface of the circular polarization antenna dielectric plate and the upper surface of the omnidirectional horizontal polarization antenna dielectric plate is 5 mm.

[0027] Figure 4 is the pattern of the combined antenna in the vertical plane. It can be seen that by introducing the circularly polarized antenna, the dip of the omnidirectional horizontally polarized antenna in the 0° direction of the vertical plane is significantly reduced, from about -27dB to about 2dB. This shows that the radiation of the circularly polarized antenna has played a good role in supplementing the blind area of the horizontally polarized antenna. Figure 5 and Figure 6 is the pattern of the combined antenna in the horizontal plane. It can be seen that the non-circularity of the combined antenna is worse than that of the single horizontally polarized antenna, but is within an acceptable range. When designing, the amplitude and phase difference between the two antennas need to be configured to balance the dip depth of the pattern and the non-circularity in the horizontal plane. The specific index depends on the requirements of the use scenario.

[0028] It should be noted that according to the needs of implementation, each step / component described in the present application can be split into more steps / components, or two or more steps / components or part of the operation of the steps / components can be combined into a new step / component, to achieve the purpose of the present application.

[0029] Those skilled in the art will readily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for designing a non-blind zone of an omni-directional horizontally polarized antenna, characterized in that, The application relates to a circularly-polarized antenna and an omnidirectional horizontally-polarized antenna. The circularly-polarized antenna is placed in parallel in the central region of the omnidirectional horizontally-polarized antenna, and the size of the circularly-polarized antenna is determined according to the principle that the radiation of the omnidirectional horizontally-polarized antenna is not blocked, so that the central axes of the circularly-polarized antenna and the omnidirectional horizontally-polarized antenna are coincident. The amplitude and phase difference of the circularly-polarized antenna and the omnidirectional horizontally-polarized antenna are configured, and the amplitude and phase difference between the circularly-polarized antenna and the omnidirectional horizontally-polarized antenna are realized through a corresponding feed network. The realization of the amplitude and phase difference between the circularly-polarized antenna and the omnidirectional horizontally-polarized antenna through the corresponding feed network comprises: Based on the fact that the omnidirectional horizontally-polarized antenna has the maximum radiation in the horizontal direction but is a radiation blind area in the vertical direction, and the circularly-polarized antenna has smaller radiation in the horizontal direction but has the maximum radiation in the vertical direction, the amplitude and phase of the feed between the omnidirectional horizontally-polarized antenna and the circularly-polarized antenna are adjusted according to the index requirements of the radiation in the horizontal direction and the vertical direction in the specific application scene, so that the direction pattern shape is adjusted and controlled. The omnidirectional horizontally-polarized antenna is in a ring type distribution, and is composed of a plurality of arc-shaped metal sheets; the end of each metal sheet is provided with a few-shaped gap for providing a periodic series capacitor and introducing a pair of parallel double wires as a balanced feed balun. The upper surface of the circularly-polarized antenna is composed of a pair of trapezoidal and rectangular composite patches and a pair of crescent-shaped patches, and the lower surface is the same as the upper surface and is placed orthogonally to the upper surface.

2. The method of claim 1, wherein, The radius of the circularly-polarized antenna cannot exceed the inner diameter of the circular ring of the omnidirectional horizontally-polarized antenna.

3. The method according to claim 1 or 2, characterized in that, The configuration principle of the amplitude and phase difference of the circularly-polarized antenna and the omnidirectional horizontally-polarized antenna is to compromise between the depth of the concave part of the direction pattern and the non-circularity in the horizontal plane.

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